The present invention relates to automatic guided vehicles (AGVs) and, more particularly, to an AGV having an interactive display for displaying diagnostic information.
In the field of material handling, most commonly in a warehouse environment, many articles must be stored in inventory and, an indefinite time later, retrieved for use. The larger the warehouse facility, the greater the number of objects that can be stored.
Moreover, large warehouse facilities require a great amount of geographical space. Not only are modern warehouses spread over a great amount of distance, but their height allows a many objects to be stacked for storage one above the other. Each object location or bin can be identified along three axes: X, Y and Z. Thus, a warehouse location for any specified particular object can be uniquely identified.
When the warehouse is large, it becomes burdensome to move material from one part of it (e.g., the port of entry) to another part thereof (e.g., a storage bin). Moreover, certain warehouses house large objects, weighing many pounds or even tons. The combination of large objects to be stored in a warehouse and great distances between pickup and delivery (P & D) stands is ideal for assigning tasks to automatic guided vehicles. As used herein, the term "assignment" indicates an address of a P & D stand for a pickup operation or for a deliver operation.
It has been found that guided vehicles moving over a buried inductive cable can perform many of the functions that humans perform without the requirement of lighting, heating, ventilation and air conditioning that would normally be required for a pleasant human work environment. Moreover, AGVs can be relied upon to operate continuously 24 hours per day. This advantage of performance over human laborers results in greater efficiency for warehouse facilities.
As AGVs become more sophisticated, they begin to acquire the attributes of intelligent robots. Monitoring the status of each AGV and diagnosing its various conditions, therefore, requires corresponding sophisticated techniques.
Heretofore, AGV indicators and displays have not been particularly user friendly. Operating status of AGVs has been determined by indicator lights, which are simply indications of whether a machine is functioning properly. Diagnostics, when performed, have to be done off line, often by using an oscilloscope and other equipment.
In certain more advanced systems, a small seven-segment display has been used to identify specific error or status conditions. For example, "E 99" might refer to a predetermined error condition. Referring to a look-up table would indicate that the vehicle had lost its guide wire, for example. Needless to say, the step of looking up such information requires time and effort taken away from system operation.